# Testing CPT Symmetry with Neutral K Mesons: A Review

## Abstract

**:**

## 1. Introduction

## 2. The Neutral Kaon System

- $\delta \ne 0$ implies CPT violation;
- $\u03f5\ne 0$ implies $\mathrm{T}$ violation; and,
- $\u03f5\ne 0$ or $\delta \ne 0$ implies $\mathrm{CP}$ violation.

#### 2.1. CPT Violation in Semileptonic Decays

#### 2.2. CPT Violation in Two Pion Decays

## 3. Experiments

## 4. “Standard” CPT Symmetry Tests

#### CPT Test from Unitarity

## 5. Tests of CPT Symmetry and Quantum Coherence

## 6. Test of CPT and Lorentz Symmetry

## 7. Direct CPT Tests in Transitions

## 8. Conclusions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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Di Domenico, A.
Testing CPT Symmetry with Neutral K Mesons: A Review. *Symmetry* **2020**, *12*, 2063.
https://doi.org/10.3390/sym12122063

**AMA Style**

Di Domenico A.
Testing CPT Symmetry with Neutral K Mesons: A Review. *Symmetry*. 2020; 12(12):2063.
https://doi.org/10.3390/sym12122063

**Chicago/Turabian Style**

Di Domenico, Antonio.
2020. "Testing CPT Symmetry with Neutral K Mesons: A Review" *Symmetry* 12, no. 12: 2063.
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